A fifth-round draft pick in 2010, Sylvester has played in 39 games in three seasons, mostly on special teams. The 6-2, 231-pounder has made one career start, that in 2011.

Sylvester missed eight games last year with a knee injury and the Steelers did not tender him an offer as a restricted free agent, making him an unrestricted free agent last month.

The re-signing of Sylvester could mean the Steelers aren’t optimistic that Sean Spence, a third-round pick in last year’s draft, has receovered from a devastating knee injury he suffered in a preseason game last August.

Pittsburgh has re-signed Larry Foote, a starter at inside linebacker the past two seasons, and hosted a number of rookie linebacker prospects already this week. The Steelers also released starting outside linebacker James Harrison last month in a salary cap-related move.

Penn State’s Michael Mauti and Clemson’s Malliciah Goodman visited the Steelers Wednesday, a day after the team had Georgia’s Jarvis Jones, Jamie Collins of Southern Mississippi and Khaseem Greene of Rutgers in for private meetings. Monday’s visitors included linebackers John Simon of Ohio State and Vince Williams of Florida State.

NFL teams are permitted to bring in 30 rookies for private meetings, though local players such as Mauti do not count against that number.

In addition to the seven linebackers, safeties Jonathan Meeks of Clemson and Phillip Thomas of Fresno State, and Texas A&M running back Christine Michael, have visited the Steelers’ facility on the South Side this week.

The rookie prospects haven’t been the only visitors.

Former Houston guard/center Antoine Caldwell, free-agent running back LaRod Stephens-Howling, a former Pitt star who has spent his NFL career with Arizona, and San Francisco linebacker Tavares Gooden have been in Pittsburgh.